Automatic telephone-testing system.



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AUTOMATIC TELEPHONE TESTING SYSTEM,

, APPLICATION FILED A`1 R.1,19o7. 1,109,960.

W. L. CAMPBELL.

AUTOMATIC TELEPHONEv TESTING SYSTEM.

APPLIGAToN HLM) APIM, 1907. E

glgggggo Patented Sept.&1914.

incasso.

narran' lstrains PATENT onirica.

"WILSON-L. ,CAMPBELL GF CHICAGO, ILLINOIS, ASSIGN'OR, BY MESNEASSIGNMENTS, i

TQ FIRST TRUST .AND SAVINGS BANK, TRUSTEE, F CHICAGO, ILLINOTS.

AUTOMATIC TELEIA-HGNE-TESTING SYSTEM.

To oZZ whom it may concern l ,Y Be it known that WILSON L. CAMPBELL,

va citizen of the United States of America tio-n is the provision ofimproved means for ,enabling an attendant at the exchange to test thesubscribers telephone lines, regardless ot whether the same are busy oridle.

Special objects of my invention are the jprovision 'of improved meanswhereby the attendant may employ' an automatic connector forautomatically establishing connection with a more or less distanttelephone line, so that he may then test the said line in the desiredmanner; the provisionsof an arrangements by which an attendant at themain or central station may. by using the connectors, test any of thetelephone lines leading into said central station, or leading to theexchange; the provision of means by which an attendant at the exchangemay employ a connector for establishing connection with the line of anysubscriber, whether the line be idle or busy, and may then shunt orshort-circuit the condelisers of the said connector, so as to ati'ord aconductively continuous circuit for testing purposes; and the provisionof certain details and features of improvement and combinations tendingto increase the general eiiciency and serviceability of a testing systemof this particular character.

In the accompanyingr drawings, Figure 1 shows diagrammatically mytesting connectory A with the' proper circuit. connections leading toAthe jacks C and C which may be located at a wire-chiefs desk.`y isconnected with the cord circuit which leads to the keys e, e'l and e'f.Of these keys .c yand c may be adapted to connect the various testingdevices usually found in a wire-chiefs desk to the line. To the key c2Specification of Letters Patent.

Application filed April l, 1907. Serial No. 365,650.

The plug -D Patented Sept. 8, 1914i.

is attached a calling device F, which in turn is normally connected withan operators set shown at H. The conductors of the plug D lead to thekey f which is adapted to place ground on either of saidconductors. Theconnector A is of the generaltype disclosed'in United States Patent No.815,176,

granted March 13, 1906, to Keith, Erickson and Erickson. At B is shown acentral source of current-supply having its positive terminal preferablygrounded at G. At I isshown a ringer generator, resented abusy-signaling machine. At L is shown a selector switch of the generaltype disclosed in United States Patent No. 815,321, granted March 13,1906, to Keith, Erickson and Erickson, allotted to the line #Q20 whichleads to the substation E. Fig. 2 is a diagrammatic perspective- View ofmy testing connector switch A,

The connector' switch Re is an improvement upon the connector switchdisclosed in said connector patent, whereby-the connector switch A maybe used for testing purposes2 as well as for establishing the linalconnection in the usual manner.v The mechanical details of the selectorL and of the connector A, as is well known, are very much the same,although there is some materialA difference in the circuits.For'instance, the connector switch shaft 2 (Fig. 2) carries the linewipers 3 and 4 and the private wiper 5. The connector switch iscontrolled by the calling subscriberfthrough the medium of the verticaland rotary line relays 6 and 7. The vertical line relay 6 directly.controls the vertical magnet S and also the rotary magnet 9.

v The function of thc vertical magnet 8 is to give the shaft andshaft,wipers a vertical motion, and the rotary magnet 9 imparts tov thesaid shaft and wipers a' rotary or circular motion. The rotary linerelay 7 controls the private magnet 10, which latter, under certainconditions, controls iii turn the ver tical and rotarymagnets 8 and 9,the release magnet 11, and also the side switch wipers 12,13, 14 and l5.The said side switch, like the usual'Y side switch, has a normal orfirst position, a second position and a third position. The. releasemagnet I11 is also controlled by ithe vertical and rotary line relaysGand 7 conjointly. By the use of the cone.l

densers 16 and 17 the connector divides the and at K is repposition thewipers 38, 39, 40 and 41 :ircuit through it into-two sections. W'hen theside switch wiper 15 is in the third position the vertical line relay 6controls the ringer relay 13 by means of which the ringer generato I maybe bridged across the line conductors ot' tbe called subscriber.l ln-Stead of the usual back-bridge release relays of the connector in thesaid patent, there are now provided the relays 19 and 20 which have oneterminal connected with. the battery lead and the other terminal leadingto the jack C (Fig. 1).

The relay 20 is adapted, upon energizing, to operate and shift thesprings 21 and 22 out of engagement with' the springs 23 and 24 and intoengagement with the springs 25 and 26. By the disen gagement of thesprings 21 vand 23, and 22 and 24, the conductors 27 and 28 aredisconnected from the vertical and rotary relays 6 andl 7 and when thesprings 2 1 and 22 engagel the springs 25 'and 26, respectively, asstated, the conductors 27 and` 28 aregmetallically connected with theshaft wipersA 3 and 4, around the condensers A16' and 17 (which dividethe circuit through vthe connector into parts) and the side switchwipers 12 and 13, thus making the said circuit through the connectorcontinuous from the conductors 27 and. 28 to the connector shaft wipers3 and 4. By this operation it will be seen that incidentally thecondensers 1.6 and 17 are short-circuited when the side switch'is inthird position. The relay 19 is adapted, when it energizes, to operatethe springs 29 and 30, thereby disconnecting the private wiper 5 fromthe side switch wiper 14. This provision is made in order that theconnector switch may call-n and not receive the busy-release on a linefor which there is a uarding potential. The said relays 19 an 20 arecontrolled only from the jack C', for when the connector is used in theordinary way there would never be any occasion tor short-circuiting thecondensers 16 and 17 or for preventing the release of the connector whena busy line is called. Furthermore, the connector is provided with anormal post arm 31 which, when the shaft 2 is raised, permits the spring32 to engage with the spring 33, whereby the busy-signaling machine K isconnected with the side switch wiper contact point 34.

T le selector switch L is Iwell known; the switch-shaft (not shown)carries the vertical and rotary wipers 35 and 36, respectively, and theprivate wiper 37. The side switch .is well known and comprises the sideswitch wipers 38, 39,40 and 41, which may be designated as the vertical,rotary 'and private side switch wipers` and the rotary magnet wiper,

respectively.

The side switch is under the control of the private magnet 42, and inits normal or first occupy the contact points 43, 44, 45 and 46,respectively. inthe second position they vrest on the contact tively,and in the third position thecontact points 51, 52, 53 and 54 are'engaged by their `respective, wipers. Through the mediumof theverticalline relay 55, and While the side switch is in first "osition, thesubscriber con trols the vertica magnet 56, which latter i operatesto'raise the switch shaft and wipers 35,l 36. and y37v vertically.

By means of the rotary line relay 57, and while the side switch is inthe first position, the subscriber controls the private magnet 42, and,therefore, the side switch. While the vside switch s is rin Vsecondposition the rotary magnet l5,8, which operates thetswitch shaft andwipers 35, 36 and 37 in a rotary direction, is energized. The verticaland' rotary line relays 55 and 57, acting 4conjointly, provide the meanswhereby the subscriber controls the release magnet 59 while the sideswitch is in the iirst or second position. If the side switch passes to`third position, then, since the selector L is of the trunk-release type,the selector is controlled points'47, 43, 49 and 50, respe@ through thenext switch, with which a con: l

nection is then established through the private wiper 37, and by meansof the backf release relay 60.? The bridge-cutoff relay 61 is adapted toopen the connection between the line relays 55 and 57 and between saidrelays and battery B. This is desirable, because if the relays are notdisconnected from each other and the battery, the ring'- ing current forsignaling the subscriber may then operate either or both ofthe relays 55and 56. and cause some interference with the switch. It is alsodesirable to remove the bridge formed through the said relays fromacross the line, to give, the voice-currents as clear a ath as possible.

The su station E in connection with which I have elected to illustratemy invention comprises a receiver 62, a switchhook 63 for controllingthe substation' circuits, which controlling operations are accomplishedthrough the medium of any suitable means, such as the cam-arms 64, 65and 66. As the switch-hook is lowered the cam-arm 64 momentarily pressesthe release springs 67,- 68 and 69 into engagement, whereby thesubstation line conductors may be grounded simultaneously. When theswitch-hook is down the cam-arm 65 engages the spring 70, therebybridging the '-T 78 by the cani-arm 66; but when the said springs aretogether ground is provided to which is secured to said impulse teethnumber ot ground. impulses,

the `called subscriber comprises by the operators incenso the groundpost 79, and to the release spring 69, as is usually the case intelephones of this type. .The said substation comprises the usualinductionlcoil having the primary Winling Tsi and secondary Winding 8l.Being an automatic substation, it is provided with the usual verticaland rotary iinpulse springs 82 and-S3. Said substation is, of course,provided with a dial (not-shown)- the shaft S4, together with thelocking dog S5. Furthermore, there is a locking cam SG that locks thedog Swllile the receiver is on the switch-hook, to prevent a rotation ofthe dial.

For operating the impulse springs 82 and -83 the substation'is providedwith an impulse Wheel 87 that is secured to the shaft S11, whichlimpulse wheel carries. on itspe-A riphery. the so-called verticalimpulse teeth 88 and one. rotary impulse tooth S9. The are so arrangedthat Whenthe dial is drawn down the impulse springs S2 und 83 are-notcarried in to'contact with the ground post 79 but as the dial returns,first the vertical teeth engage the vertical impulse spring S2, andafter' they have completed their worlr the rotary impulse. tooth 89operates the rotary impulse spring ln this operation the subscribersvertical line conductor '90 is rst given c andthen the rotary lineconductor 91 is given one ground impulse. T-

the dial is out of normal position the con struction is such that thedog peiinits'the primary circuit springs 92 end 93 to sepa-v` rete, thuspreventing-the impulses that are delivered toeither line conductor frompass'- ing to the other.

f Means whereby. the subscriber mcy signal the push-l button spring 9ewhich normally engages. the Contact point 95; but when the button ispressed the-spring 9d engages the Contact pointQtS, whereby the verticalline conductor' maybe grounded. .l

he operation of my testing connector is. as follows: Suppose that it isvdesired to establish connection with the line conductors 90 and 91loading to the substation E. The attendantinserts thc plug l) into thejack C, thereby placing inf-engagement the tip 97, ysleeve 98 and ring 09 of the plug D Ywith the tip spring 100, sleeve spring 101 and jackring 1 02 of the jaclrC.

The engagement of the rings 102 and 99 places a guarding potential onthe private the substation E stood, of course,

twice, and the rotary line ,it will be seen thatv cs 'long 'conductor103 which' protects the trunk conductors 27 and 2S. The attendant Athenopferates the key c2, placing'. in contact the springs 106` and 107 ,and10S and 109, Where# set H, inseries with the calling device F, isbridged across the conluctors 104. and 10:3 which lead to thetr'unlrconductors 27 and 28..' To call the number 220, which, it is assumed,jisthe number of the substation E, the attendent operates the callingdevice for the last two digits (2 and 0) only; for the calling device isheady in connect-ion with ductors2'? and 28, and/the e'ect of groundingthe line for the last two digits operates the connector. -It will beevident that it an-` other subscribcrat a substation similar to he Wouldhave topperate a first-selector, and that would require onedigit. yThefirst-so lector vvouldplace him in connection with the connector A, orsonie'other connector oi ythe seme group, already stated, to two digitsto complete the desired con nection. It is obvious, therefore, thatsincev the calling device F is already in direct connection with theconnector With the substation v#220. Itvvill be underthat anysubscriber, in tryingA to call the substation #220, operates his dialfor said first digit 2 oel line conductonO of the -substation E)vconductor (similar tothe rotary 'lineconductor 91) once.. The resultis, linereley 55 isoperated twice,-.and the shaft otithe selector israisedtvro steps to the second' level, .citer which operation 'the*impulse ,thst comes in over thefrotary linestarts the the connectortrunk con- 7o were to call the number 220, 75

which connector requires, as 8O an operation corresponding A, the lirstdigit y 85 vmust be omitted in making the connection andggrcunds his 90.vertical line conductor (similar to the vertiae' ulredyknown, thatftlievertical 95 selector rotating automatically until an idle trunk line-isfound, the conductors of which,

such'as the conductors` 27, 28 and 103, lead te soon'neetor .A or someother connector. The operator'omits the lirst digit and takes up thecell yfrom the second 1digit2 the button 110 is pressed and the spring111 iscarried outl of engagement :With-the Contact point 112 and intoengagement with the ground post111'3. Thisresults y.in grounding theconductor energizing circuit is closed through the verjticalline-relay6. This circuit extends from g groimd G through the ground post 1,?13,spring 111, springs 106 and 107, through the' digit 2. Forthis 104,whereby 'an 110 Etip: 97 to the spring 100, conductor '104, U5

trunk conductor 27, springs 21 and 23, vertical. line relay 6 to/thebattery lead 114, gthence. through battery B to ground G. :Each timethat the vertical line relay 6l is energ'ized the line relay `arepressedinto Contact, thereby olosingan.y energizing circuit through thevertical mag-- net 8 which operatesin the usual manner, one 'step atatime, tocarry 4the Ashaft Wipers',v 3, land 5 which arelocatedthejnormal; terminalsbf` the'line.f#22 0. i They .energizingcircuit .for the vertical 'magnetinay :bei traced .from ground GFIthroughthe'springs lland 115, through the springs and 11G 120 two stepsopposite lthe level in 1275 private magnet springs A140 and 141, conducytor 142 to the side switch Wiper 15, contact point 143 to the verticalmagnet 8, thence to the battery lead 114', and through battery B fi toground G. When the button 117 is A/pressed the spring 118 disengagesfrom the contact point 119 and makes contact with theground post 113,thereby closing an enlfergizing circuit through the rotary line relay 7,said circuit extending from ground Gr through the ground post 113 andspring 119.#

. springs 108 and 109, sleeve-98 to the sleeve spring 101, conductor105, trunk conductor 28, springs 22 and 24, through the rotary linerelay 7 to the battery lead 114, thence through battery B to ground G'.The rotary line relay, upon operating, closes an energizing circuitthrough thel private magnet 10l which operates to release the connectorside switch from iirstto second position.

' The energizing circuit for the private magnet may be traced asfollows: From ground G5 through the springs 116 and 144 to the privatemagnet 10, thence to the battery lead 114, and through battery B4 toground G. The last digit being naught, the calling device is operated,as previously described., grounding the vertical conductor 27 ten timesandl the rotary line conductor 28 once. The Vertical and rotary linerelays 6 and 7 are operated over .previously traced circuits. However,When the line relay springs and 116 engage, a circuit is then closedthrough the rotary magnet 9, instead of through the vertical magnet 8,as follows: From ground G5 through the springs 116 and 115, as above,and through the private magnet springs 1.40 and 141 to the side switchWiper 15, thence through the contact point 145 to the rotary magnet 9,thence to the battery lead 114, and through batteryl B to ground G. Eachtime that the rotary magnet is energized it operates to rotate the shaft2 and shait wipers 3, 4 and 5, one step at a time, until the said wipersare carried into engagement with the normal conductors 120, 121 and 122,the former two of which lead to the line terminals of the desiredsubscriber.

The energizing of the rotary line relay 7, as previously stated,completes an energizing circuit through the private magnet 10 which nowoperates to release the side switch from second to third position, thus.

placing the side switch Wipers 12, 13, 14 and 15 in Contact with theirrespective contact points 128, 124, and 126. Furthermore, when the sideswitch wiper 14 engages the contact point 125 a guarding potential isestablished 'for protecting the called line. This potential extends fromground G2 to the Contact point 125, side switch wiper 14, through thesprings 29 and 30 to the private wiper 5 which engages the privateContact of the called line. Also the passage of the 1yr-fiancee,

side stv fiper 14 to third position closes an ener0 eircult through thebridgecut-ot rllayl @1l of the selector L This circuit extends froi theside switch ground G2 t0 the private Wiper' Si, over the guardingpotential circuit already traced to the private normal conductor 122,through the switch shaft springs 146 and 147 Vof the first-selector L tothe bridge-cutoii relay 61, thence to the battery lead 114 and 7 throughbattery B to ground G. The line conductors 90 and 91 of the substation#220 are now extended to the jack C. The attendant may nonv insert theplug D into the jack C,.after restoring the key e2, and establishconnection with the relays 19' and 20.

By means of the key f an energizing circuit is then established throughthe relay 20, said circuit extending from ground G3 85 through thesprings 127 and 128, through the sleeve 129 to the sleeve spring 130,con-- dnetor 131, through the relay 2,0 to the battery lead 114, thencethrough battery B to ground G. The said relay, upon energizing, operatesto shift the springs 21 and 22 from the springs 23 and 24 to the springs25 and;4 26. The engagement of the said spring closes a short-circuit orshunt around thi condensers 16 and 17. The attendant may then operatothe test keys e, e', etc., to perform any desired test on the lineconductorswith which the connector shaflt Wipers 3 and 4 are inconnection. Should the attendant desire to signa] the subscriber atsubstation lo #22() the key is lirst restored to normal position, thusbreaking the energizing circuit through the relay 20, `which in turnremoves the shunt from around the c0ndensers 16 land 17, and the key c2is again 10.".` operated; then the button 11() is pressed, whereby thespring 111 is pressed into engagement With the ground spring 113 wherebyan energizing circuit is established through the connector vertical linerelay 6, 118 as before. The Vsaid relay now operates to close anenergizing circuit through the` ringer relay 18, which operates in theusual manner to bridge the ringer generator I across the line conductors90 and 91 to oper- 111. ate the ringer 71 at substation E.

The energizing circuit through the ringer relay 18 extends from groundG5 through the springs 116 and 115` andthrough the private springs and141 to the side 129 switch Wiper 15, thence to the .contact point 126,through the ringer relay 18 to the battery lead 114. and through battiry'B to ground G. When the ringer relay 18 encrgizes, the springs 148 and149 are discon- 125 nected from the line conductors 27and 28, on thecalling side, by leaving the springs 15s() and 151, respectively, andare carried into engagement with the springs 152 and 158 that constitutethe terminals of the 1" r10, and through battery lead 114. thencethrough lzxttery B crates to release the connector wiper 14.

Licence? ringer generator the said last-named springs, and throughductors and 91, and through the ringer 71, while the' switchhoolr G3 isdown. The subscriber at substation E, upon removing the receiver 62'from the switch-hook 63, mayl converse with the attendant over thecircuit shown by the heavy lines. The release of the connector by theoperator at H may be brought about when the springs 111 and 118 arepressed onto the ground post 113 simultaneously if `the lrey e2 isthrown, thereby grounding both conductors 27 and 28 Simultaneously,which closes an energizing circuit through both vertical and rotaryrelays il and 7 simultaneously, which operate to place the springs 132and 133 in contact. An energizing circuit is thereby established throughthe release magnet 11, Said circuit extending from ground G4 through thering 99 of the plugD 'to'. the ring 102 of the'jack C, conductors 134and 103, trunk-release springs 132 and 133, re`- leasemagnet 11 to thebatteri;7 leed 114, thence through battery B and to ground G. Therelease magnet 11, upon energizing, 0p-

switch and restore'th'e shaft wipers 3, 4 and to normal positionA byattracting the armature 15e, which'then 'strikes' the double dog 155 tothe right of the pivotsI 156, so as to remove the said donble dog fromengagement with the shaft 2, and s0 as to, at the seme time, drive thesidev switch back to its normal position throng, .the medium of the sideswitch link -157 that. connects the double dog with the side switch. isdeprived double dog by the .coiled spring which is provided for thatpurpose and which is indicated et the top of the shaft.

'Ordina-rily, if any. connector is operated tocelle line that is busy,and the private wiper 5 is, therefore, rotated into eng-agement with abusy line, then when the last Of course, as soon as the sheft of thesupport provided by the Irotary ini'pulse comes in and the private'-inagnet is energized and carries the private springs 158 and 159 intoengagement, the

potential that protects the busy line esteblishes 1an energizingcurrent-through the release magnet 11 that Hows from the' busy Contactthrough the private wiper, through.- the relay springs 30 and 29.y sideswitch (in second position), private springs 159 and 158 of the privatemagnet the release magnet 11 to the Atogroluld G. The release magnetthen, upon energizing, deprives the switch shaft of itsl support andalso restores the 'side 'switch l'. The ringing current `then passes outfrom the generator 1 throught.

it is restored to normal position,

to. lirst: position,

' condition. y

Suppose that iii-1s desired,V for any reason,

line whichvis protected by a guarding po- 1tential. In ,thatl eyent theattendant open.. ates the key toclosej the 'springs 135"and 13G incontact,whereby an energizing circnit is closed through the relay 19extend? ing from ground GG through they springs 135 and` 136, tip 137 ofthe plugD, tip spring l138, conductor; 139,

battery B to ground G. yThe said relay,

upon energizing, operates' to disengage ther l springs29 and 30, wherebythe priva-teshaft, wiper 5 is disconnected from the side'switch wiper1d. Now, when the shaft Wiper 5 engages acontact point .upon whichthereis a guarding potential,- the' connector` is' not which' operationfbreaksjtlle Q, y i y ,estabhshedfenergizmg circuitV for the releasemagnet,- re'storn'g the'v connector to normal 4701.1 :to call-inon aline that'is busy`that is, a f

lay 19 to the battery lead 114C, thence'throl'lghSO given the so-calledbusy-release, forthel pro.-

tecting potential isf'not" transmitted to the. release magnet llwhenthe'private 'magnet 10 energizes on theA lastAv rotary in'rpi'se.

Therefore,

by meansiof .the 'connector A. the.v f

attendant may establishconnection with. a n.. i,

line when it is protectedvby' guarding po#` tential. To do so he wouldtake the precaution to throw the key f While he is rnaling.:A A,

e call, so that when the last'rotary impulse 'cornes in, the circuitthat would ordinarilyv cause the busy-release of the connector-'isinterrupted at e point between the springsA 29 and means for preventingthe busy-release', .and the means toriestnblishing ay metallic 'circuit39 of the reley 19. The aforesaid f from the caliingl-to thecalledfside, around thecondensers 16 endl', are all controlled'.-

J'roin the jack C which is under the super'- visienof the attendent.-

tfwill also be understeod, ofcourse, that ,f ,l

thev connector having' these special provi sions cen be used' by'thesubscrib'ers for establishing ordinary connections, end for l suchpurposes the subscribers uee the regu?.

le'rtrunl: linesileading'to the connectors.

ALs illustrated, there are two 'jacks for each l connector th'ns'equipped with means for test/ing the telephonelines, one' jaclr being'v.connected with trunk line leadingto such connector, and

the other jack being connected with the spe-9 cial or additional trunkline which lends to the regular or oi'dinnry said connector. Theattendenttesting a linewill, therefore. pluginto tlie jack connectedwiththe regu-lar trunk line leading tof-the afterward will also plug'connector, end into the jeclr connected with the conductors, such, forezgainple, as' the4 conductors 131 and 139, for the purpose4 of'shunti-nlg or shortcircuiting the-condehsers the connector', aspreviously explained. it wilbe understood niet my nepwveetegdeeinfringement can be used in systems Where the connectors and individualswitches andy automatic selectors are all located at one and the samecentral station; for even in such case the attendant can then test thelines Without leaving his desk or switchboard. These connectorsare notnecessarily all at the same station.

The trunking can be arranged on a percentage basis-that is to say, theconnectors can be less in number than the total number of subscribers,and the selectors can be employed on the same basis. rlhe subscribersindividual switches Will, With such arrangement, be the only switches inthe eX- change Which are the same in number as the subscribers lines. Inan exchange of ten thousand subscribers, divided into groups of onehundred subscribers each, there Will then be one testing connector foreach group of one hundred lines, and each testing connector can be oneof the regular ten connectors allotted to the group of one hundredsubscribers. lt Will be understood,of course, that the connectors arenot necessarily ten per cent of the total number of subscribers, as theycan be either more or less, according to requirements. As explained, thespecial or additional apparatus of each testing connector does not inany Way interfere with its use by the subscribers for ordinary purposes.i

It will be understood, of course, that the conductors X shown in Fig. llea-d back to an automatic selector, or some other suitable mechanism orapparatus, and that through the mediuml of these conductors the callingsubscriber can control the connector A to seize an idle line. Throughthe medium of the manual switchboard, however, and the attendantscalling mechanism thereon, said connector can be controlled to seizeeither a busy or an idle line. The said connector is always controlledover the three-Wire trunk comprising the three conductors leadingthereto, the third conductor of which is included in the trunk releasecircuit of the connector. In this Way the trunk release circuit mayinclude a contact of the jack, or may include contacts in the selectoror other apparatus by which a calling subscriber extends connection tothe said connector.

It will be seen that the automatic connectors herein disclosed are ofthat type in which the line Wipers have vertical vor straight motion toselect groups, and rotary motion to connect with a line in the selectedgroup, the system being of that character in which the subscribers aredivided into lgroups. Each level or horizontal row of .liuc contacts inthe connector represents a certain group of subscribers, and after theconnector has been operated vertically or in a straight line to selectthe required level or group, it is then given a rotary motion to'Licence ind and connect with a line in the selected group. v

'Vlhat l claim as my invention is l. An automatic telephone exchangesystem comprising a connector switch, telephone lines terminating atsaid switch, means by Whichy an attendant may cause said connectorswitch to seize any one of said lines, condensers in the said connector,and means controlled by the said attendant vfor shunting orshort-circuiting said conconnector to vseize a busy line.

3. An automatic telephone exchange system comprising telephone lines,means for rendering one or more of said lines busy, an automaticconnector, means for preventing seizure of a busy line by a connectorWhenthe latter is used by a subscriber, a i

manual switchboard, and means controllable from the said switchboard forcausing theconnector to seize a busy line.

a. An automatic telephone exchange system comprising telephone lines, anautomatic connector, a trunk line leading to said connector, meansbywhich calling subscribers ioo may use said trunk .line for operatingsaid connector to establish connection with a called telephone line, amanual switchboard provided with a jack connected with said trunk line,another j ack on said switchboard having direct conection With saidconnector, means for rendering one or more of said telephone lines busy,means controlled through the medium of said first-mentioned jack foroperating said connector, condenscrs in said connector, and meanscontrolled through the medium oi said last-mentioned jack for enablingthe connector to seize. a busy line, and for shunting orshort-'circuiting said condensers to aliord a eonductively continuouscircuit for testing purposes.

5. In a telephone system, the combination of telephone lines, anautomatic connector, a trunk line leading to said connector, a springjack connected with said trunk line, a special trunk line leading to said cor.- nector, a spring jack :f or said special trunk line, a callingdevice and a telephone andmeans for connecting the same with saidrst-mentioned jack, and suitable instrumentalities controllable throughthe medium of said last-mentioned jack for enabling incasso vided intogroups, comprising telephone lines, means for rendering one or more ofraid lines busy, an automatic connector, means for preventing seizure ofa busy line by a connector when the latter is used by a subscriber, a`manual switchboard, and means controllable from the said switchboardlfor causing the connector to seize a busy line, the said connectorprovided with means llaving straight motion to select groups and rotarymotion to connect with a line in the selected group.

18. An' automatic telephone exchange ,synF tem in which the subscriberslines are di vided into groups, comprising telephone lines, an automaticconnector, a trunk lino leading to said connector, means by whichcalling subscribers may use said trunk line for operating said connectorto establish connection with a called telephone line, the said connectorprovided with means hav-- ing straight motion to select groups androtary motion to connect with a line in the sclected group, a manualswitchboard provided with a jack connected with said trunk line, anotherjack on said switchboard having direct connection with said connector,means for rendering one or more of said telephone lines busy, meanscontrolled through the medium of said first-mentioned jack for operatingsaid connector, condensers in said connector, and means controlledthrough the medium of said last-mentioned jack for en# abling theconnector to seize a busy line, and for shunting or shortcircuiting saidcon densers to 'afford a conductively continuous circuit for testingpurposes.

19. In a telephone system in which the subscribers lines are dividedinto groups, the combination of telephone lines, an automatic connector,a trunk line leading to said connector, a spring jack connected withsaid trunk lines, a special trunk line leadingv to said connector, aspring jack for said special trunk line, a calling device and atelephone and means for connecting the same with said first-mentioned"jack, and suitable instrumentalities controllable through the medium ofsaid last-mentioned jack for enabling the connector to seize a busytelephone linefand establish 'a conductively continuous circuit fortesting` purposes, the said connector provided with means havingstraight mot-ion to select groups and rotary motion to connect with aline in the selected group.

20. ln a telephone system in which the subscribers lines are dividedinto groups, the combination of telephone lines, an automatic connector,a pair of voice-current condoctors and a special release trunk conductorleading to said connector, the said connector provided withl meanshaving straightmotion to select groups and rotary motionl to connectlwith a line in the selected group, a spring jack having contactsconnecte said connector for controlling purposes, and a spring Jackconnected with said last-men tioned pair of conductors, said springjacks f associated together at a point remote from said connector, andcords and plugs for establishing connection with said connector throughthe medium of said jacks.

21. In a telephone system in which the subscribers lines are dividedinto groups, a tlg" nli'line comprising the conductors 'havling .oneZend thereof terminating in a connector and another end terminating inthe bank contacts of a selector switch, the said con- Rector providedwith means having straight motion to select groups and rotary motion toconnect with a line in the selected group, a jack allotted to saidtrunk, a plug allotted to said jack, means whereby when the plug isinserted in the jack the said trunk line is made busy, and means inconnection with the plug whereby the connector may be operated toestablish connection with un automatic line.

22. In a telephone system in ,which the subscribers lines are divided.into groups, a connector, a pair of jacks` a plug for cach oli saidjacks, a calling device and testing' ap paratus associated with one ofsaid plugs, a rotary back-bridge relay and a vertical bock. bridge relayallotted to the connector, means associated with the other of 'saidplugs .whereby either the vertical or the rotary back-bridge relays maybe energized, and line relays allotted to the connector and adapted tobe operated by the said calling device for establishing connection',with a called line, the said connector provided with means havingstraight motion to select groups and rotary motion to connect with aline in the selected group.

23. In ya telephone system in which the snbscriberslines are dividedinto groups, the combination ot a connector and a jack, the saidconnector provided with means` having straight motion to' select groupsand ro tary motion to connect with a' line in the se- ,looted group, aprivate circuit, a pair ot condensers, a rotary back-bridge relay, andaverti'cal back-bridge relay allotted to the connector, a-plug allottedtothe jack, means associated with said plug, whereby either the verticalor rotary baclrebridge relays may be operated, the former for opening upthe private circuit of the connector, whereby said 'connector may be putin condition toA ycall ona busy line, and the latter adapted toberenergized to short-circuit said condensers.

24. In a telephone system in which the subscribers lines are dividedinto groups, a connector, a trunk line terminating therein, a jackallotted to said trunk, a plug allotted with 4to said jack, testingmeans allotted to said plug, a rotary back-bridge relay aliotted to saidconnector, means whereby the connector may be operated to seizel orconnect with a line, the said connector provided with means havingstraight motion to select groups and rotary motion to connect With aline in the selected group, condensers al lotted to said connector, onein each side of the talking circuit, and means whereby the said rotaryback-bridge relay may be energized to short-circuit said condensers,.vhereby the seized line may be extended by nietallic circuit to theplug for the purpose of testing.

25. In a telephone system in which the subscribers lines are dividedinto groups, an automatic connector, the said connector provided withmeans having straight motion to select groups and rotary motion toconnect with a line in the selected group, telephone lines, means forrendering some of said lines busy, a three-Wire trunk leading to saidconnector, and means for inanually connecting with ,said trunk to causethe connector to seize either a'busy or an idle line.

QG. In a telephone system, subscribers lines divided into groups, anautomatic connector', the said connector provided vvitl` means havingstraight motion to select groups and rotary motion to connect with aline in the selected group, a manual switchboard, and means forcontrolling said connector from said switchboard to connect vvith eithera busy or an idle line.

2?. in a telephone system, subscribers lines divided into groups, anautomatic connector, the said connector provided with means havingstraight motion to select groups and rotary motion to connect with aline in the selected group, means by which a calling subscriber may usesaid connector for seizing an idle line, a manual switchboard, and meanson said switchboard for controlling said connector to cause the latterto seize either a busy or an idle line,

28. A telephone system in which the subscribers lines are divided intogroups, comprising an automatic connector, the said connector providedwith means having straight motion to select groups and rotary motion toconnect with a. line in the selected group, telephone lines, means bywhich a calling subscriber controls said connector to seize an idleline, and means by which an attendant controls said connector to seizeeither a busy or an idle line.

2Q. In a telephone system, an automatic connector, telephone linesdivided into groups, means for rendering some o-said lines busy, athree-.aire trunk leading to said connector, and mear for manuallyconnecting with said trunlt to cause the ccnnector to seize either abusy or an idle line, said connector having vertical motion to selectgroups and rotary motion to [ind the called line in any selected group.

.in a telephone system, an automatic connector, telephone lines dividedinto groups, a manual switchboard, and means i'or controlling saidvconnector from said switchboard to connect with either a busy or anidle line, said connector having one motion to select groups and secondmotion to find the called line in any selected group. 3l. ln a telephonesystem, subscribers lines divided into groups, an automatic testingapparatus comprising a plug and jack and connector, and means operative'through the plug and jack for connecting the connector with either abusy or an idle teicphone line, .said connector having vertical motionto select groups and rotary motion to ind the called line in anyselected group, substantially as shown and described Signed by nie atChicago, Cook county, illinois, this 26th day of -March, 1907.

WILSON L, @A ./PBELL.

Witnesses EDWARD D. Frites, Annina B. Srnnnr,

